2022-08-25_PERMIT FILE - C1981012 (20)

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The water pipelines and the associated control wiring will be upgraded. The potable water system will consist of a 2 -inch fusion joint HDPE DRI 1 AWWA C906 pipe. The mine drainage water system will consist of 10 -inch fusion joint HPDE DRI IAWWA C906 and 8 inch schedule 40 -flanged steel pipe and fittings AWWA D-100 beginning at vault -6 and continuing in a trench to vault 5 and 3. The raw water system will consist of 16 inch HDPE DRI 1 AWWA C906 and 12 inch Schedule 40 flanged steel pipe and fittings beginning at vault 6 and continuing in a trench to vaults5 and 3. Pipe vaults are concrete construction pre -cast where possible. Vault 5 is cast in place adjacent to the existing mine portal. Hydrants are strategically located throughout the surface facilities to provide water for fire fighting. Electric and control wiring is required in the utilities corridor up to the tanks to control valves and provide water level data. Typical vault construction details are included as Figure 2a. An emergency escape hoist will be added to the east portal exhaust shaft. The hoist consists of a shuttle cage with hoist and controls. The hoists have independent power sources for emergency operation. It may be necessary to replace the vane axial fan at the West Portal with a centrifugal fan capable of operating at higher pressures. The 600 hp fan requires an enlarged foundation and electric power. The overhead power line will be extended from the East portal substation to the West portal. As the mine works advance dewatering of the old Allen works is necessary for the protection of the workers. Due to the geometry and the structure of the old works, two additional mine dewatering holes will be needed. Each borehole will be constructed and permitted through the Colorado Division of Water Resources. Each hole requires the installation of a pump. The pumps require electric distribution to the location. The Bates Portal will be located southeast of the silos. The portal face up requires about a 45 Ft high cut. Cut slopes in common material are excavated 1.5H: IV. Cut slopes in rock are excavated at a 0.25H:1 V. Rock bolts; wire mesh and shotcrete will be used as necessary to stabilize the cut slope. A soil nail wall will be constructed to increase the size of the portal bench. Three declined slope entries were driven in an easterly direction approximately 425 feet to the Blue Seam. Blue Seam was approved by Technical Revision #58(TR-58). Structures to be installed at the Bates Portal include a ventilation fan, conveyer drive building, transfer building, 72 -inch wide beltlines and retaining walls. A 240 -foot long (100 feet in by and 270 feet out by) 72 -inch portal beltline will exit the portal and terminate at the transfer tower. A second 600 Ft long 72 -inch wide beltline will convey coal in a westerly direction from the transfer tower to the existing breaker building. Three retaining walls along the north side of the access road average about eight feet high and are a total of 285 feet long. A detailed listing of the size of the foundations of all buildings and proposed construction type is included in Exhibit 28 - Bond Calculations. Section 2.05 RN -6 10/17/2016